Thermodynamic analysis of chemically reacting mixtures – comparison of first and second order models

journal article in Web of Science

English

Recently, a method based on non-equilibrium continuum thermodynamics which derives thermodynamically consistent reaction rate models together with thermodynamic constraints on their parameters was analyzed using a triangular reaction scheme. The scheme was kinetically of the first order. Here, the analysis is further developed for several first and second order schemes to gain a deeper insight into the thermodynamic consistency of rate equations and relationships between chemical thermodynamic and kinetics. It is shown that the thermodynamic constraints on the so-called proper rate coefficient are usually simple sign restrictions consistent with the supposed reaction directions. Constraints on the so-called coupling rate coefficients are more complex and weaker. This means more freedom in kinetic coupling between reaction steps in a scheme, i.e., in the kinetic effects of other reactions on the rate of some reaction in a reacting system. When compared with traditional mass-action rate equations, the method allows a reduction in the number of traditional rate constants to be evaluated from data, i.e., a reduction in the dimensionality of the parameter estimation problem. This is due to identifying relationships between mass-action rate constants (relationships which also include thermodynamic equilibrium constants) which have so far been unknown.

affinity; entropic inequality; independent reactions; kinetics; rate constants; rate equations; thermodynamics

PEKAŘ, M.

1. 3. 2018

Frontiers

2296-2646

Frontiers in Chemistry

6

35

Swiss Confederation

1

7

7

http://journal.frontiersin.org/article/10.3389/fchem.2018.00035/full

http://hdl.handle.net/11012/84117